Attachments for orthopedic implants

ABSTRACT

Apparatuses, kits, and methods for cementing an orthopedic implant to a bone, post attachment, are disclosed in some aspects of the present disclosure. A kit can include a prosthetic component and a cement applicator. The prosthetic component can include an attachment profile that corresponds to a mating profile formed on or in a bone. The cement applicator can be configured to apply a bone cement between the bone and the prosthetic component following alignment between the prosthetic component and the bone or another prosthetic component. The kit can also include a bone cement. A method can include positioning the prosthetic component adjacent to the bone, aligning the prosthetic component relative to the bone or another prosthetic component, and applying a bone cement between the bone and the aligned prosthetic component.

CLAIM OF PRIORITY

This patent application is a divisional Ser. No. 15/041,706, filed onFeb. 11, 2016, which is a continuation of U.S. patent application Ser.No. 13/774,629, filed on Feb. 22, 2013, now issued as U.S. Pat. No.9,295,554, which is a continuation-in-part of U.S. patent applicationSer. No. 13/545,119, filed on Jul. 10, 2012, each of which are herebyincorporated by reference herein in its entirety, and the benefit ofpriority of each of which are hereby claimed.

BACKGROUND

Prosthetic components are available, for example, to replace bodilycomponents or portions of bodily components that cannot be regeneratedor are no longer functioning properly. Examples of prosthetic componentsinclude heart valves, pacemakers, collagen for soft tissue augmentation,and orthopedic components, such as fracture plates and artificial knee,hip, and ankle joints.

SUMMARY

One aspect of the present disclosure provides a method for attaching aprosthetic component to a bone. This particular method includes a stepin which a prosthetic component with an attachment profile is provided.In another step, a mating profile is formed in a bone of a patient.Thereafter, the prosthetic component is positioned adjacent the bonewith the attachment profile associating with the mating profile in amale-female mating relationship that leaves at least one open spacebetween the prosthetic component and the bone. In another step, abiocompatible adhesive material is delivered into the at least one openspace.

In another aspect, the present disclosure provides a prosthesis that ispositionable between a first bone surface and a second bone surface in apatient. The prosthesis includes a first prosthetic component andstackable, second prosthetic component that is stackable onto the firstprosthetic component. The first prosthetic component includes a firstattachment profile that is associable with a mating profile of the firstbone surface in a male-female mating relationship and a secondattachment profile that is associable with a mating profile of thesecond bone surface in a male-female mating relationship. The secondprosthetic component includes an attachment profile that replicates thefirst attachment profile of the first prosthetic component to allowassociation with the mating profile of the first bone surface in amale-female mating relationship and a mating profile that replicates themating profile of the first bone surface to allow association with thefirst attachment profile of the first prosthetic component in amale-female mating relationship.

The present disclosure, in certain other aspects, is directed toapparatus, kits, and methods for the implantation and stabilization ofan orthopedic implant to a bone using a filler material such as bonecement. The apparatus, kits, and methods of certain embodiments of thepresent disclosure can include the use of a cement applicator, such as asyringe, to deliver the bone cement or a cement precursor to one or moredesired locations between a prosthetic component of an orthopedicimplant and a bone to which the prosthetic component is attached. Use ofthe cement applicator in such instances allows a surgeon or othermedical practitioner to insert, position, align, and attach theprosthetic component prior to the application of bone cement, allowingfor appropriate component positioning or alignment and cleanerapplication of the bone cement, e.g., a bioabsorbable bone cement.

A kit can include a prosthetic component including an attachment profilecorresponding to a mating profile formed on or in a bone, and a cementapplicator configured to apply a bone cement between the bone and theprosthetic component, following alignment between the prostheticcomponent and the bone or a second prosthetic component.

A method of implantation can include positioning a prosthetic componentadjacent to a bone, aligning the prosthetic component with respect tothe bone or with respect to another prosthetic component, or both, andapplying a bone cement between the bone and the aligned prostheticcomponent.

A kit can include a disclosed prosthetic device for positioning adjacentto a bone, aligning with respect to the bone or with respect to anotherprosthetic device, or both, and attaching to the bone, and cement forapplying between the bone and the aligned and attached prostheticdevice.

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings, like numerals can be used to describe similar elementsthroughout the several views. Like numerals having different lettersuffixes can be used to represent different views or instances ofsimilar elements. The drawings illustrate generally, by way of example,but not by way of limitation, various embodiments discussed in thepresent document.

FIG. 1 is a schematic view of an example orthopedic ankle implantpositioned in a patient.

FIG. 2 is a close-up schematic view of an example orthopedic ankleimplant having bone cement applied between a bone and a prostheticcomponent of the orthopedic ankle implant.

FIG. 3 is an isometric view of an example orthopedic ankle implant.

FIG. 4 is a schematic view of an example orthopedic ankle implant havingbone cement being applied between a bone and a prosthetic component ofthe orthopedic ankle implant using a cement applicator.

FIG. 5 is a flow chart of an example method of implanting an exampleprosthetic component.

FIG. 6 is a flow chart of an example method of implanting an orthopedicankle implant including two or more prosthetic components.

FIG. 7 is a close-up schematic view of another example orthopedic ankleimplant.

FIG. 8 is a close-up schematic view of an example ankle fusion device.

DETAILED DESCRIPTION

The present disclosure, in certain aspects, includes apparatuses, kits,and methods for the implantation and affixing of a prosthetic componentof an orthopedic implant to a bone using bone cement. These particularapparatuses, kits, and methods can include the use of a cementapplicator, such as a syringe, to deliver a bone cement or a cementprecursor to one or more desired locations between a prostheticcomponent of an orthopedic implant and a bone to which the prostheticcomponent is attached. Use of the cement applicator can allow a surgeonor other medical practitioner to insert, position, and align theprosthetic component to a bone prior to the application of bone cement.In contrast, existing implantation methods include the application ofbone cement, if at all, either to the prosthetic component or to thebone prior to inserting the prosthetic component into the patient, oftenleading to bone cement being inadvertently spread to unintended orundesirable locations or hardening (e.g., setting) prior to propercomponent positioning and alignment, all while operating under thetiming duress imparted by a limited working time of the cement.

The present apparatus, kits, and methods can provide for the use of lesscement and can provide for less cement clean-up compared to existingmethods of bone cement application. Additionally, the present apparatus,kits and methods can allow for alignment of the prosthetic componentprior to application of the bone cement, thereby allowing for moreprecise placement and alignment of the prosthetic component. Moreover,because bone cement can be precisely applied using the present cementapplicator, the bone cement can be applied to locations that willincrease the chances of fixation of the prosthetic component to thebone.

In various examples, the present apparatus, kits, and methods can beused with orthopedic implant systems (e.g., ankle joints, wrist joints,elbow joints, knee joints, hip joints, shoulder joints, finger joints,toe joints, and in a variety of fusion and fusion-type devices includingones utilized in and around the above joints and elsewhere in theskeletal system including in the spine) where bone cement is desirablefor fixation and stabilization of a prosthetic component to a bone,particularly when precise application of bone cement is difficult due tospace constraints. An example of an orthopedic implant system in whichthe present apparatus, kits, and methods can be used is an orthopedicankle implant, such as an implant that may be used for total anklearthroplasty (“TAA”) surgery, also known as total ankle replacement. Anankle implant used for TAA surgery is often inserted through an anterioror lateral ankle arthrotomy. A small portion of bone, such as a smallportion of a tibia and/or a talus, can be removed to make room for oneor more components of the ankle implant. The portion of bone that isremoved from the tibia and/or talus is often only a centimeter or lessin thickness, and the implant components to be inserted can be onlyslightly smaller, if at all, than the vacated space.

FIG. 1 is a schematic view of an example orthopedic ankle implant 10positioned within a patient 1. Bones located within the leg, foot, andankle of the patient 1 include the tibia 2, the talus 4, and the fibula6. The ankle implant 10 can comprise a tibial component 12 and a talarcomponent 14. The tibial component 12 can be affixed to a distal portionof the tibia 2 and the talar component 14 can be affixed to a proximalportion of the talus 4. The ankle implant 10 can further comprise abearing component, such as a polymeric bearing component 16, positionedbetween the tibial component 12 and the talar component 14 and providingan articulating surface. An example of a material that can be used toform the bearing component 16 is ultra-high molecular weightpolyethylene (UHMPWPE). For example, the bearing component 16 can becoupled to the tibial component 12 on a first surface and can articulateagainst the talar component 14 on a second surface.

An exemplary ankle implant for use with the present apparatuses, kitsand methods is shown and described in U.S. Pat. Nos. 7,625,409;7,963,996; 7,025,790; and 7,238,190, all of which are herebyincorporated by reference in their entirety.

Each of the tibial component 12 and the talar component 14 can comprisean attachment profile or feature(s) corresponding to a mating profile orfeature(s) formed in the tibia 2 and the talus 4, respectively. In FIG.1, for example, the attachment profile of the tibial component 12 issubstantially analogous to the mating profile of the tibia 2 allowingthe tibial component 12 to fit with the tibia 2 in a keyed arrangement.Similarly, the attachment profile of the talar component 14 can besubstantially analogous to the mating profile of the talus 4 allowingthe talar component 14 to fit with the talus 4 in a keyed arrangement.The mating profiles of the tibia 2 and the talus 4 can also each includeone or more cavities, void spaces, or other female-type mating featuresin addition to its other mating surfaces. A bone cement can be preciselyapplied in and/or on the cavities, void spaces, or other features of themating profile after the components 12, 14 have been inserted into thepatient 1 or attached to the tibia 2 or talus 4, respectively, for addedstability.

FIG. 2 is a close-up schematic view of the example implant 10 of FIG. 1.Prior to insertion of the ankle implant 10, a space can be formedbetween the tibia 2 and the talus 4 through the manipulation of a tibialdistal surface 3 or a talar proximal surface 5, or both. The space canbe formed by removing a portion of the tibia 2 to form the distalsurface 3 and expose a proximal end of the talus 4, or it can be formedby removing a portion of the talus 4 to form the proximal surface 5 andto expose a distal end of the tibia 2, or both. The tibial component 12can he inserted into the vacated space so that a proximal surface 18 canbe positioned adjacent to the tibial distal surface 3, and the talarcomponent 14 can be inserted into the vacated space so that a distalsurface 20 is positioned adjacent to the talar proximal surface 5.

The tibial component 12 can comprise an attachment profile on itsproximal surface 18 that can correspond to a mating profile of thetibial distal surface 3. One of the profiles of the tibial component 12and the tibial distal surface 3 can comprise a male feature and theother can comprise a mating female feature. The attachment profile ofthe tibial component 12 can include at least one male feature. The malefeature can comprise a rail 22 protruding from the proximal surface 18of the tibial component 12. The mating profile of the tibial distalsurface 3 can comprise at least one mating female feature, including arecess 24 sized to receive the projecting rail 22.

Similarly, the talar component 14 can comprise an attachment profile atits distal surface 20 that can correspond to a mating profile of thetalar proximal surface 5. One of the profiles of the talar component 14and the talar proximal surface 5 can comprise a male feature and theother can comprise a mating female feature. The attachment profile ofthe talar component 14 can include at least one male feature. The malefeature can comprise a rail 26 protruding from the distal surface 20 ofthe talar component 14. The mating profile of the talar proximal surface5 can comprise at least one mating female feature, including a recess 28sized to receive the projecting rail 26. Male features other than rails,such as ribs, fins, or keels, can also be used for the tibial component12, the talar component 14, or both.

The bearing component 16 can be coupled or attached to the tibialcomponent 12 or to the talar component 14. The bearing component 16 canbe attached to either component 12, 14 with a mechanical attachmentdevice, such a snap fit between the bearing component 16 and the tibialcomponent 12 or the talar component 14,

Bone cement can be applied between a prosthetic component of an implantand a corresponding bone to which the component is attached. Forexample, as illustrated in FIG. 2, a bone cement 30 can be appliedbetween the tibial component 12 and the tibia 2, or between the talarcomponent 14 and the talus 4, or both. Using the present teachings, thebone cement 30 can advantageously be applied only to localized, desiredlocations between each component 12, 14 and the corresponding bone 2, 4.For example, the bone cement 30 can be applied in an interface betweenmale features and female features of the prosthetic components 12, 14and bones 2, 4. The recesses 24, 28 can be prepared and sized so thatthey provide space for the rails 22, 26, with additional space to form acavity for the bone cement 30. Such additional spaces can be shaped andsized in any suitable manner to suit a particular orthopedicapplication. For example, the female-like void space 21 shown in FIG.2substantially mimics the shape of the rail so as to provide asubstantially uniform thickness to the void space surrounding the rail.The bone cement 30 can be applied only or substantially only withinrecesses 24, 28 respectively existing between a projecting rail 22 ofthe tibial component 12 and the tibial distal surface 3 and between aprojecting rail 26 of the talar component 14 and the talar proximalsurface 5. This sort of limited and targeted application of bone cementand/or other void-filling biocompatible material at the implantationsite can be particularly useful in situations as described herein belowwhere a highly porous, bone ingrowth-receptive material providesbone-contacting surfaces 18, 20 and rails 22, 26. In this regard, thecement or other void-filling material can help to facilitate attachmentof the implant to the surrounding bone while also leaving substantialportions of the highly porous, bone-contacting surfaces free of cementor filler and directly open to bone ingrowth.

FIG. 3 is an isometric view of a plurality of components of an ankleimplant 10. As illustrated, one or more projecting rails 22 can extendlaterally across a proximal surface 18 of a tibial component 12. Atleast one projecting rail 22 can extend substantially entirely across alateral width of the tibial component 12. Similarly, one or moreprojecting rails 26 can extend laterally across a distal surface 20 ofthe talar component 14. Al least one projecting rail 26 can extendsubstantially entirely across a lateral width of the talar component 14.The ankle implant 10 can further comprise a bearing component 16positioned between the tibial component 12 and the talar component 14.The bearing component 16 can provide an articulating surface to theankle implant 10. Other configurations of male features and femalefeatures can be used. For example, rather than laterally projectingrails 22, 26, the components 12, 14 can include rails, ribs, fins, orkeels that extend from the anterior to the posterior and thecorresponding recesses formed in the tibia 12 and the talus 14 can beformed to extend from the anterior to the posterior.

FIG. 4 is a schematic view of a tibial component 12, a talar component14, and a bearing component 16 of an ankle implant 10 inserted into apatient 1, such as through an incision 32 in a leg of the patient 1.Bone cement 30 can be locally applied using a cement applicator 34, suchas a syringe or a dispenser comprising an applicator nozzle 36, on or ina feature of a prosthetic component or a bone to which the prostheticcomponent is to be attached. The space between the tibial component 12and the tibia 2, or between the talar component 14 and the talus 4, orboth, can be small, e.g., as small as from 1 millimeter to 2millimeters. The cement applicator 34 allows a surgeon or other medicalpractitioner to precisely and locally apply bone cement 30 within thesmall space, such as in recesses 24, 28 and/or on rails 22, 26. In theexample of the ankle implant 10 illustrated in FIG. 4, the cementapplicator 34 can be used to apply the bone cement 30 into the recesses24 to affix the tibial component 12 to the tibia 2 and into the recesses28 to affix the talar component 14 to the talus 4.

The tibial component 12, the talar component 14, and a bearing component16, if included, can be inserted into a vacated space between the tibia2 and the talus 4. Each component 12, 14 can be positioned or alignedwith respect to the bone 2, 4 to which it is to be affixed (e.g., sothat a position or alignment of the prosthetic component 12, 14 withrespect to the bone 2, 4 is substantially similar to a desired finalposition or alignment) before applying the bone cement 30. For example,after being inserted into the patient 1, the tibial component 12 can bepositioned and aligned with respect to the tibia 2 or with respect tothe talar component 14. A frame, jig, or other support means can be usedto maintain the relative position of the tibial component 12 withrespect to the tibia 2 or the talar component 14. The cement applicator34 can be used to dispense the bone cement 30 into the cavity or spaceformed between the recesses 24 and the projecting rails 22. Similarly,after being inserted into the patient 1, the talar component 14 can bepositioned and aligned with respect to the talus 4 or with respect tothe tibial component 12. A frame, jig, or other support means can beused to maintain the relative position of the talar component 14 withrespect to the talus 4 or the tibial component 12. The frame, jig, orother support means that is used with the talar component 14 can be thesame or different frame, jig, or other support means that is used withthe tibial component 12. The cement applicator 34 can be used todispense the bone cement 30 into the space between the recesses 28 andthe projecting rails 26.

In an example, the mating profiles in the tibia 2 and the talus 4 can beformed so that an interference fit can be formed between the attachmentprofile of the tibial component 12 and the mating profile of the tibia2, or between the attachment profile of the talar component 14 and themating profile of the talus 4. An interference fit can allow thecomponents 12, 14 to remain in a desired alignment relative to acorresponding bone 2, 4 without the need of a frame, jig, or othersupport means. A user can place the component 12,14 in position andalign the component 12, 14 relative to the bone 2, 4, and then engagethe component 12, 14 with the bone so that the interference fit canform. The interference fit can then hold the component 12, 14 in placeand maintain the alignment until the bone cement 30 can be applied.

For example, an interference fit can be created by forming the recesses24 and 28 in the tibia 2 and talus 4, respectively, to have a width atone or more positions that is slightly larger than a corresponding widthof the corresponding projecting rail 22 or 26. In an example, aninterference fit can be formed between a male feature and a femalefeature if a width at one or more positions of the female feature, suchas the recesses 24, 28, is within 0.5 millimeters (mm) (about 0.0197inches) of a width at a corresponding one or more positions of the malefeature, such as the rails 22, 26. The interference fit can also beformed if a width at one or more positions of the female feature iswithin 0.45 mm (about 0.018 inches), within 0.4 mm (about 0.0157inches), within 0.35 mm (about 0.014 inches), within 0.34 mm (0.0134inches), within 0.33 mm (about 0.13 inches), within 0.32 mm (about0.0126 inches), within 0.31 mm (about 0.0122 inches), or within 0.3 mm(about 0.0118 inches), such as about 0.28 mm (about 0.011 inches).

The attachment profile or a portion of the attachment profile of thecomponents 12, 14 can also be formed from a material or have a structurethat provides for an interference-type of attachment to bone, such as aporous scaffold, for example a porous metal such as porous tantalum. Oneor more of the rails 22, 26, or at least a portion of the surfaces 18,20, or both, can be formed from a porous scaffold (e.g., a highly porousscaffold) to facilitate attachment of the components 12, 14 to the tibia2 and the talus 4, respectively. In an example, substantially all ofsurfaces 18, 20 and rails 22, 26 can be formed of a porous metalmaterial. The porous metal material can be bonded (e.g., diffusionbonded) or otherwise attached to a metal substrate that forms theremainder of each component 12, 14. For example, as probably best shownin FIG. 3, tibial component 12 in this particular illustrativeembodiment, can include a base tibial-side substrate 23 that is fused(e.g., welded) or otherwise coupled to a highly porous, boneingrowth-receptive structure 25 which in this instance providesbone-contacting surfaces 18 and rails 22. Likewise, talar component 14can include a base talar-side substrate 27 that is bonded to a highlyporous, bone ingrowth-receptive structure 29 which in this particularinstance provides bone-contacting surfaces 20 and rails 26. Examples ofmaterials that can be used to make a substrate (e.g., substrates 23 and27) to which a porous metal scaffold, such as a porous tantalumscaffold, is coupled include, but are not limited to, titanium (Ti),cobalt-chrome (CoCr), tantalum and alloys thereof such as cobaltchromium molybdenum. According to an exemplary embodiment of the presentdisclosure, the substrate may be a Ti-6Al-4V alloy, such as Tivanium®which is available from Zimmer, Inc., of Warsaw, Ind. Tivanium® is aregistered trademark of Zimmer, Inc.

Highly porous metal structures such as structures 25 and 29 canincorporate one or more of a variety of biocompatible metals. Suchstructures are particularly suited for contacting bone and soft tissue,and in this regard, can be useful as a bone substitute and as cell andtissue receptive material, for example, by allowing cells and tissue togrow into the porous structure over time to enhance fixation (i.e.,osseointegration) between the structure and surrounding bodilystructures. Bone cements and other biocompatible void-filling materialsdisclosed herein can also interdigitate into the pores of these highlyporous structures to facilitate attachment of these structures tosurrounding bone and/or other implant components. According to certainembodiments of the present disclosure, an open porous metal structuremay have a porosity as low as 55%, 65%, or 75% or as high as 80%, 85%,or 90%, or within any range defined between any pair of the foregoingvalues. An example of an open porous metal structure is produced usingTrabecular Metal™ Technology available from Zimmer, Inc., of Warsaw,Ind. Trabecular Metal™ is a trademark of Zimmer, Inc. Such a materialmay be formed from a reticulated vitreous carbon foam substrate which isinfiltrated and coated with a biocompatible metal, such as tantalum, bya chemical vapor deposition (“CVD”) process in the manner disclosed indetail in U.S. Pat. No. 5,282,861 and in Levine, B. R., et al.,“Experimental and Clinical Performance of Porous Tantalum in OrthopedicSurgery”, Biomaterials 27 (2006) 4671-4681, the disclosures of which areexpressly incorporated herein by reference. In addition to tantalum,other biocompatible metals may also be used in the formation of a highlyporous metal structure such as titanium, a titanium alloy, cobaltchromium, cobalt chromium molybdenum, tantalum, a tantalum alloy,niobium, or alloys of tantalum and niobium with one another or withother metals. It is also within the scope of the present disclosure fora porous metal structure to be in the form of a fiber metal pad or asintered metal layer, such as a Cancellous-Structured Titanium™ (CSTi™)layer. CSTi™ porous layers are manufactured by Zimmer, Inc., of Warsaw,Ind. Cancellous-Structured Titanium™ and CSTi™ are trademarks of Zimmer,Inc.

Generally, a highly porous metal structure will include a largeplurality of metallic ligaments defining open voids (i.e., pores) orchannels therebetween. The open spaces between the ligaments form amatrix of continuous channels having few or no dead ends, such thatgrowth of soft tissue and / or bone through open porous metal issubstantially uninhibited. Thus, the open porous metal may provide alightweight, strong porous structure which is substantially uniform andconsistent in composition, and provides a matrix (e.g., closelyresembling the structure of natural cancellous bone) into which softtissue and bone may grow to provide fixation of the implant tosurrounding bodily structures. According to some aspects of the presentdisclosure, exterior surfaces of an open porous metal structure canfeature terminating ends of the above-described ligaments. Suchterminating ends can be referred to as struts, and they can generate ahigh coefficient of friction along an exposed porous metal surface. Suchfeatures can impart an enhanced affixation ability to an exposed porousmetal surface for adhering to bone and soft tissue. Also, when suchhighly porous metal structures are coupled to an underlying substrate, asmall percentage of the substrate may be in direct contact with theligaments of the highly porous structure, for example, approximately15%, 20%, or 25%, of the surface area of the substrate may be in directcontact with the ligaments of the highly porous structure.

An open porous metal structure may also be fabricated such that itcomprises a variety of densities in order to selectively tailor thestructure for particular orthopedic applications. In particular, asdiscussed in the above-incorporated U.S. Pat. No. 5,282,861, an openporous metal structure may be fabricated to virtually any desireddensity, porosity, and pore size (e.g., pore diameter), and can thus bematched with the surrounding natural tissue in order to provide animproved matrix for tissue ingrowth and mineralization. According tocertain embodiments, an open porous metal structure may be fabricated tohave a substantially uniform porosity, density, and/or void (pore) sizethroughout, or to comprise at least one of pore size, porosity, and/ordensity being varied within the structure. For example, an open porousmetal structure may have a different pore size and/or porosity atdifferent regions, layers, and surfaces of the structure. The ability toselectively tailor the structural properties of the open porous metal,for example, enables tailoring of the structure for distributing stressloads throughout the surrounding tissue and promoting specific tissueingrown within the open porous metal.

In other embodiments, an open porous metal structure may comprise anopen cell polyurethane foam substrate coated with Ti-6Al-4V alloy usinga low temperature arc vapor deposition process. Ti-6Al-4V beads may thenbe sintered to the surface of the Ti-6Al-4V-coated polyurethane foamsubstrate. Additionally, another embodiment of an open porous metalstructure may comprise a metal substrate combined with a Ti-6Al-4Vpowder and a ceramic material, which is sintered under heat andpressure. The ceramic particles may thereafter be removed leaving voids,or pores, in the substrate. An open porous metal structure may alsocomprise a Ti-6Al-4V powder which has been suspended in a liquid andinfiltrated, and coated on the surface of a polyurethane substrate. TheTi-6Al-4V coating may then be sintered to form a porous metal structuremimicking the polyurethane foam substrate. Further, another embodimentof an open porous metal structure may comprise a porous metal substratehaving particles, comprising altered geometries, which are sintered to aplurality of outer layers of the metal substrate. Additionally, an openporous metal structure may be fabricated according to electron beammelting (EBM) and/or laser engineered net shaping (LENS). For example,with EBM, metallic layers (comprising one or more of the biomaterials,alloys, and substrates disclosed herein) may be coated (layer by layer)on an open cell substrate using an electron beam in a vacuum. Similarly,with LENS, metallic powder (such as a titanium powder, for example) maybe deposited and coated on an open cell substrate by creating a moltenpool (from a metallic powder) using a focused, high-powered laser beam.

Examples of porous scaffolds for prosthetic implants, such as orthopedicbone restoration or joint repair implants, are described in theaforementioned U.S. Pat. No. 5,282,861 to Kaplan, entitled “Open CellTantalum Structures For Cancellous Bone Implants and Cell and. TissueReceptors,” and U.S. Provisional Patent Application Ser. No. 61/653,510,entitled “ANISOTROPIC POROUS SCAFFOLDS,” filed on May 31, 2012, whichare incorporated herein by reference in their entireties. A porousscaffold is available under the aforementioned trade name TRABECULARMETAL™ from Zimmer, Inc., Warsaw, Ind., USA, such as for orthopedicimplants. The porous structure of a porous scaffold can also provide forcement adhesion to the components 12, 14.

The cement applicator 34 can comprise a needle or nozzle 36 having asmall cross-sectional width at a tip 38, thereby allowing the tip 38 anda portion of the needle or nozzle 36 to fit within a profile feature ofeither a prosthetic component, such as the tibial component 12 or thetalar component 14, or a bone to which the prosthetic component is to beattached, such as the tibia 2 or the talus 4. In an example, the needleor nozzle 36 is sized and shaped to fit into a recess formed betweenmale and female features, such as between one of the rails 22 of thetibial component 12 and a corresponding recess 24 within the tibia 2.The needle or nozzle 36 can also be sized and shaped for insertion intoa first lateral end of a recess 24, 28 and across the desired width to amedial end of the recess 24, 28.

In addition to, or as an alternative to bone cement 30, a variety ofbioabsorbable and non-bioabsorbable void-filling materials can hedelivered to recesses and other open spaces or voids that are providedadjacent a prosthetic component as disclosed herein such as recesses 24,28. Illustratively, the bone cement 30 can be any adhesive materialconfigured for adequately stabilizing a prosthetic component to a bone.An example bone cement is a polymeric bone cement, such as a polymethylmethacrylate (“PMMA”) cement. The bone cement 30 can be formed from acement precursor 40 comprising one or more materials that undergopolymerization or cross-linking to form a solid or substantially solidbone cement 30, when cured. The cement precursor 40 can be formed bymixing a liquid monomer with a particulate or powdered copolymer, Afterthe liquid monomer and the copolymer are mixed and applied, the liquidmonomer can undergo a polymerization reaction, such as a free-radicalpolymerization, to form the solid or substantially solid cement 30.

A liquid monomer that can be used is, but is not limited to, methylmethacrylate monomer. Examples of a particulate or powdered copolymercan include, but are not limited to, polymethyl methacrylate and methylmethacrylate-styrene. Other compounds, such as a polymerizationinitiator or a polymerization accelerator, can be mixed with the liquidmonomer and the particulate or powdered copolymer when forming thecement precursor 40,

After being formed, the bone cement 30 or cement precursor 40 can beloaded into the cement applicator 34 and dispensed between a prostheticcomponent and a bone. In an example, the cement precursor 40 beginspolymerizing, or setting, soon after the liquid polymer and theparticulate or powdered copolymer are mixed. Alternatively, the cementprecursor 40 can remain substantially in liquid form for a period oftime sufficient to apply it in desired void locations using the cementapplicator 34. In various examples, the materials forming the cementprecursor 40 are selected so that the bone cement 30 will not set (e.g.,will not be fully polymerized) for from about 3 minutes to about 5minutes after mixing. The bone cement 30 or cement precursor 40 can havea viscosity conducive to its application from a needle or nozzle 36having a profile or cross section that is sized and shaped to fit into arecess formed between male and female features, such as between one ofthe rails 22 of the tibial component 12 and a corresponding recess 24within the tibia 2. In an example, the cement precursor 40 is configuredso that the viscosity of the cement precursor 40 remains below athreshold viscosity for at least a period of time that is sufficient toapply the cement precursor 40 through the cement applicator 34 into oneor more desired locations, such as within a recess 24, 28. In anexample, the cement precursor 40 has a viscosity below the thresholdviscosity for from about 3 minutes to about 5 minutes after the cementprecursor 40 is formed.

The threshold viscosity that is acceptable can depend on severalfactors, including the geometry of the cement applicator 34, thegeometry of the needle or nozzle 36 and the tip 38, the geometry of thespace into which the bone cement 30 or cement precursor 40 is to beapplied, and the physical makeup of the bone cement 30 or cementprecursor 40 (e.g., the particle size of the copolymer, the weightpercent of the copolymer in the cement precursor mixture, or thecomposition and weight percent of additives in the cement precursormixture).

An example of a suitable bone cement 30 that can be used is OSTEOBOND®copolymer bone cement, manufactured by Zimmer, Inc., of Warsaw, Ind.,USA.

The prosthetic component or components described herein, such as thetibial component 12 and the talar component 14, can be combined in a kitwith a cement applicator configured to apply a bone cement between thebone and the prosthetic component, following alignment of the prostheticcomponent with the bone, or engagement between the attachment profile ofthe prosthetic component and the mating profile of the bone, or both.The kit can also include a separate or integral sterile package for oneor more of the kit components, such as the prosthetic component orcomponents and the cement applicator. The kit can also comprise a bonecement or a cement precursor to be applied between the bone and theprosthetic component. The kit can also comprise a frame configured tomaintain a position or an alignment of the prosthetic component withrespect to the bone or with respect to a second prosthetic component.The kit can also include instructions for a user, such as to performsome or all of the steps of the method or methods described below.

FIG. 5 is a flow chart of an example method 50 of affixing a prostheticcomponent, such as a tibial or talar component of an orthopedic ankleimplant, to a bone, such as a tibia or a talus. The method 50 cancomprise, at 52, exposing a portion of one or more bones to be modified(e.g., the tibia and the adjacent talus) by one or more prostheticcomponents, such as by cutting through the skin, muscle, and othertissue of a patient. At 54, a profile in the bone can be formed to matewith an attachment profile of the prosthetic component. The profile inthe bone can be a reverse or mirror image of the attachment profile ofthe prosthetic component. Forming the profile can comprise forming afeature in the bone that corresponds to a feature of the attachmentprofile of the prosthetic component, such as forming a female feature inthe bone, such as a recess, configured to receive or mate with a malefeature of the prosthetic component, such as a projecting rail, a fin, arib, or a keel.

At 56, the prosthetic component can be positioned adjacent to the bone,and, at 58, the prosthetic component can be aligned with respect to thebone or with respect to another prosthetic component. Positioning oraligning the prosthetic component allows a user to assure that analignment or position of the prosthetic component with respect to thebone or with respect to the other prosthetic component is substantiallythe same as a desired final position or alignment of the prostheticcomponent, such as the desired position or alignment of the tibialcomponent with respect to the tibia or the talar component afteraffixing the tibial component to the tibia. Positioning the prostheticcomponent can comprise inserting the prosthetic component into thepatient, for example through an incision. Positioning the prostheticcomponent can also comprise engaging an attachment profile of theprosthetic component with the corresponding mating profile of the bone.The term “engaging,” as used herein with respect to a prostheticcomponent and a corresponding bone, can refer to positioning one or morefeatures of the attachment profile of the prosthetic component so thatthey are in substantially the same position as a corresponding matingfeature or features of the profile of the bone. For example, theprosthetic component can be positioned so that the attachment profilefits with the bone in a keyed relationship. As shown in the ankleimplant of FIGS. 1-4, the attachment profile of the tibial component cancomprise one or more male features in the form of projecting rails, andthe mating profile of the tibia can comprise a corresponding recess foreach projecting rail.

After positioning or aligning the prosthetic component, or both, themethod 50 can include, at 60, a bone cement can be applied between aportion of the positioned or aligned prosthetic component and the bone.Application of the bone cement can comprise dispensing a cementprecursor into a void between the attachment profile of the prostheticcomponent and the mating profile of the bone. The cement precursor canbe applied in or on a feature of the bone, or in or on a feature of theprosthetic component, or both. At 62, the prosthetic component can beaffixed to the bone with the bone cement. The bone cement can bepassively allowed to set or harden in order to affix the prostheticcomponent to the bone, or the bone cement can be actively set, such aswith an activatable initiator, such as a photoinitiator.

Application of the bone cement can comprise injecting or dispensing thecement precursor with a cement applicator, such as the exampleapplicator illustrated in FIG. 4. The cement applicator can beconfigured to dispense the cement precursor to a localized and desiredlocation, such as between a rail of the tibial component and a recess inthe tibia through a nozzle or a needle conduit and with little to nocement leakage. The cement applicator can allow for the application ofthe cement precursor after the tibial component, for example, has beeninserted into the patient, positioned with respect to the tibia or thetalar component, aligned with respect to the tibia or the talarcomponent, yet still ensure that the cement precursor and the resultingbone cement is adequately applied at desired locations.

Application of the cement precursor between the prosthetic component andthe bone to which the prosthetic component is to be attached cancomprise substantially filling a female feature of the prostheticcomponent and/or the hone with the cement precursor. In an example wherea female feature comprises a recess, the method can comprise filling therecess substantially across an entire medial length of the recess withthe cement precursor. Each female feature can be filled using aretrograde fill method. “Retrograde filling” can refer to a method wherethe bone cement or cement precursor is dispensed as the applicator iswithdrawn from the female feature, such as by inserting the nozzle ofthe applicator into a first lateral end of the recess and across thelateral width of the recess to a second lateral end of the recess,followed by withdrawing the nozzle from the recess while concurrentlydispensing the cement precursor through the nozzle. In an example, thecement precursor can be dispensed or prepared so that the female featureis substantially free of entrapped air.

The method 50 can further comprise forming the cement precursor prior todispensing. Forming the cement precursor can comprise mixing a liquidmonomer, such as methyl methacrylate, with a particulate or powderedcopolymer, such as a powdered polymethyl methacrylate or a powderedmethyl methacrylate-styrene. Other additives can he mixed with themonomer and the copolymer, such as a polymerization initiator or apolymerization accelerator. Mixing the liquid monomer and theparticulate or powdered copolymer can result in a polymerizationreaction, such as free-radical polymerization, to form a solid orsubstantially solid bone cement.

The method 50 can comprise loading the cement precursor into the cementapplicator. In an example, loading the cement precursor into the cementapplicator can include removing or evacuating any air from the cementapplicator, such as by inverting the cement applicator and thendispensing the air and a small amount of the cement precursor from thecement applicator prior to applying the cement precursor between theprosthetic component and the bone.

After applying the cement precursor between the prosthetic component andthe bone, the method 50 can further comprise removing excess cementprecursor or bone cement so that the excess bone cement does notinterfere with operation of the implant or contaminate the surgicalsite. After the bone cement has set, stability, strength, or both, ofthe bone cement and the prosthetic component can be tested,

FIG. 6 is a flow chart of an example method 70 of positioning anorthopedic ankle implant, for example, into a patient, to replace ajoint. At 72, a joint that is to be modified by one or more prostheticcomponents can be exposed.

Exposing the ankle joint can comprise cutting through the patient'sskin, muscle, and other tissue, and resecting and pulling back bodilytissue.

At 74 the joint can be prepared for modification, such as by cleaningout extraneous material or tissue. Preparing the joint can also includeremoving a portion of one or more bones, such as the tibia and thetalus, in order to make room for one or more prosthetic components ofthe implant. Removing portions of the one or more bones can includestabilizing a patient's extremity of interest using a frame, jig, orother support apparatus, followed by cutting or resecting a portion ofone or more of the bones.

At 76, at least one feature can be formed in a first bone of the joint.At 78, at least one feature can be formed in a second bone of the joint.Each feature that is formed can correspond to an attachment feature of acorresponding prosthetic component.

At 80, a trial reduction of the prosthetic components can be performed,such as by inserting a temporary or trial version of each component ofthe final prosthetic implant into the patient to test for an acceptablesize and geometry. In the case of an ankle implant, for example, a trialtibial component with a geometry similar to that of a final tibialcomponent, a trial talar component with a geometry similar to that of afinal talar component, and a trial bearing component with a geometrysimilar to that of a final bearing component can be inserted into thepatient, positioned, and aligned in much the same way that finalcomponents can be aligned. A surgeon or other medical practitioner canthen inspect the trial components and the corresponding bones todetermine if the fit and alignment of the trial components is acceptable(e.g., ensuring that there is no lateral overhang of the trials beyondthe tibia or the talus, ensuring that there is no bony impingement bythe fibula., ensuring that the trial tibial component is substantiallyflush with the tibia, or ensuring that the trial talar component issubstantially flush with the talus). If the fit or alignment of thetrial components is not acceptable, the trial components can be removed,and one or more trial components of a different size or shape can beinserted or the bones can be further manipulated,

At 82, a first prosthetic component can be positioned in the patient sothat each attachment profile feature of the first prosthetic componentis adjacent to, or engaged with, a corresponding formed mating profilefeature in the first bone. Similarly, at 84, a second prostheticcomponent can be positioned in the patient so that each attachmentprofile feature of the second prosthetic component is adjacent to, orengaged with, a corresponding formed mating profile feature in thesecond bone. The first and second final prosthetic components that areselected and positioned within the patient can each have a geometry thatis identical or substantially identical to a geometry of thecorresponding trial component that was found to provide for anacceptable fit during the trial reduction, at 80.

At 86, the first prosthetic component can be aligned with respect to abone, such as the first bone, or with respect to another prostheticcomponent, such as the second prosthetic component. Similarly, at 88,the second prosthetic component can be aligned with respect to a bone,such as the second bone, or with respect to another prostheticcomponent, such as the first prosthetic component. In the case of theankle implant, for example, the tibial component can be aligned withrespect to the tibia, with respect to the talar component, or withrespect to the bearing component. Similarly, the talar component can bealigned with respect to the talus, with respect to the tibial component,or with respect to the bearing component. Aligning each component cancomprise securing each component with one or more frames, jigs, or othersecuring apparatus to adjust and maintain the alignment of eachcomponent.

At 90, a bone cement or a cement precursor can be applied between thefirst prosthetic component and the first bone and. Similarly, at 92, thebone cement or the cement precursor can be applied between the secondprosthetic component and the second bone. In the case of the ankleimplant, for example, the bone cement or the cement precursor can beapplied between the tibial component and the tibia or between the talarcomponent and the talus.

At 94, the bone cement between the first prosthetic component and thefirst bone can be set in order to affix the first prosthetic componentsto the first bone. Similarly, at 96, the bone cement between the secondprosthetic component and the second bone can be set in order to affixthe second prosthetic component to the second bone. Setting the bonecement can comprise allowing the bone cement to set without active steps(e.g., allowing a cement precursor to polymerize and set as a solid orsubstantially solid bone cement to set). Alternatively, setting the bonecement can comprise actively causing or initiating setting via the useof a heat-activated cement precursor that begins setting upon theapplication of heat above an activation temperature or anultraviolet-activated cement precursor that begins setting upon exposureto ultraviolet light of specified wavelength. While the cement precursoris setting to form the bone cement, the position and alignment of theprosthetic components with respect to the bones can be maintained, suchas through continued use of a frame, jig, or other securing apparatusthat holds one or more prosthetic components in position or alignmentwith respect to one or more bones or one or more other prostheticcomponents.

The steps of the method 70 can generally be performed in any order,except where the ordering of steps is necessitated. For example,although the flow diagram of FIG. 6 illustrates, at 76, forming at leastone feature in the first bone before forming at least one feature in thesecond bone, at 78, these steps can be performed in a reverse order.Moreover, each step involving the first prosthetic component and thefirst bone can be performed in their entirety without performing thesteps involving the second prosthetic component and the second bone, andvice versa. For example, a method can comprise, at 76, forming at leastone feature in the first bone, e.g., the tibia, corresponding to atleast one mating feature in the first prosthetic component, e.g., thetibial component, then, at 82, positioning the tibial component, e.g.,adjacent to or engaged with the tibia, then, at 86, aligning the tibialcomponent with respect to the tibia or with respect to anotherprosthetic component, then, at 90, applying a bone cement or cementprecursor between the tibial component and the tibia, then, at 94,setting the bone cement between the tibial component and the tibia.After completing these method steps with respect to the first prostheticcomponent, the method can then include performing the steps with respectto the second prosthetic component, e.g., at 78, forming at least onefeature in the second bone, e.g., the talus, corresponding to at leastone mating feature of the second prosthetic component, e.g., the talarcomponent, then, at 84, positioning the talar component, e.g., adjacentto or engaged with the talus, then, at 88, aligning the talar componentwith respect to the talus or with respect to another prostheticcomponent, then, at 92, applying a bone cement or cement precursorbetween the talar component and the talus, then, at 96, setting the bonecement between the talar component and the talus.

With reference now to FIG. 7, shown is an example ankle implant similarto that shown in FIG. 2 except additionally incorporating a stackablemember 100 stacked atop tibial component 12. Stackable member 100 can beformed with a variety of biocompatible implant materials, and in thisparticular illustrative embodiment is formed with a highly porousmetallic material that is particularly adapted to receive bony ingrowth.Illustratively, at this particular treatment site, the tibial component12 includes an attachment profile on its proximal surface 18 thatcorresponds to a mating profile of a distal surface 102 of the stackablemember 100, whereas the stackable member 100 includes an attachmentprofile on its proximal surface 104 that corresponds to a mating profileof the tibial distal surface 3. As discussed herein above, such profilescan incorporate cooperating male and female features. Male or male-typeelements can include rails, ribs, fins, keels, and other projections. Inthis instance, male-type rails similar to rails 22 shown in FIG. 2protrude from tibial component proximal surface 18 and from stackablemember proximal surface 104. Female-type recesses are located instackable member distal surface X and in tibial distal surface 3 foraccommodating the rails while leaving additional space to form a cavityfor bone cement and/or another biocompatible filler material assimilarly discussed elsewhere herein.

The talar component 14 is similar to that shown in FIG. 2, and includesan attachment profile with projecting rails at its distal surface 20.These rails can be received in recesses in the talar proximal surface 5where the recesses can provide space for the rails with additional spacefor filler material(s). In an alternative embodiment, a second stackablemember (not shown) can be stacked below talar component 14. Such amember can be similar to member 100 except being ratable with the distalsurface of the talar component 14 including its rails and with the talarproximal surface 5 including its recesses. This second stackable membercan be incorporated into the overall implant in addition to or insteadof stackable member 100, and in this regard, it will be understood that,to suit a particular orthopedic application, any suitable number ofsuccessive stackable members can be stacked adjacent tibial component 12and/or talar component 14. Also, any two such stackable members in animplant arrangement can be the same or different in terms of physicalcharacteristics such as but not limited to shape, size, thickness, andmaterial(s) of construction.

With reference now to FIG. 8, shown is an example of an ankle fusiondevice 110 according to one embodiment of the present disclosure. Thisand other fusion devices disclosed herein could be similar adapted foruse elsewhere in the skeletal system including but not limited to in thefoot, hand, and spine. This particular fusion device is formed with ahighly porous metallic material that is particularly adapted to receivebony ingrowth although it can be formed with any number of suitablefusion-facilitating materials. Illustratively, at this particulartreatment site, the fusion device 110 includes an attachment profile onits proximal surface 112 that corresponds to a mating profile of thetibial distal surface 3 and an attachment profile on its distal surface114 that corresponds to a mating profile of the talar proximal surface5. As discussed herein above, such profiles can incorporate cooperatingmale and female features. Male or male-type elements can include rails,ribs, fins, keels, and other projections. In this instance, male-typerails similar to rails 22 shown in FIG. 2 protrude from fusion deviceproximal surface 112 and from distal surface 114. Female-type recessesare located in tibial distal surface 3 and talar proximal surface 5 foraccommodating the rails while leaving additional space to form a cavityfor bone cement and/or another biocompatible filler material assimilarly discussed elsewhere herein.

In an alternative embodiment, one or more stackable members (not shown)similar to the stackable members discussed above in relation to FIG. 7can be stacked atop fusion device proximal surface 112 and/or one ormore stackable members can be stacked below fusion device distal surface114 to provide a stacked, multi-part fusion device. Any suitable numberof stackable fusion members can be employed in this regard to suit aparticular orthopedic application. Illustratively, a first stackablemember can be stacked atop fusion device proximal surface 112 with theattachment profile of this proximal surface corresponding to a matingprofile of a distal surface of the first stackable member. The firststackable member can then include an attachment profile on its proximalsurface that corresponds to a mating profile of the tibial distalsurface 3. As discussed herein above, such profiles can incorporate avariety of cooperating male and female features including but notlimited to rails and rail-accommodating recesses as shown in FIG. 8, Anytwo such stackable members in a stacked, multi-part fusion arrangementcan be the same or different in terms of physical characteristics suchas but not limited to shape, size, thickness, and material(s) ofconstruction.

To better illustrate the apparatus, kits, and methods and disclosedherein, a non-limiting list of examples is provided here:

Example 1 can include subject matter (such as an apparatus, a device, amethod, or one or more means for performing acts), such as can include akit. The subject matter can comprise a prosthetic component including anattachment profile corresponding to a mating profile formed on or in abone, and a cement applicator configured to apply a bone cement betweenthe bone and the prosthetic component, following alignment between theprosthetic component and the bone or another prosthetic component.

Example 2 can include, or can optionally be combined with the subjectmatter of Example 1, to optionally include the prosthetic componentbeing a first prosthetic component and the bone being a first bone.

Example 3 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1 or 2, to optionallyinclude a second prosthetic component including an attachment profilecorresponding to a mating profile formed in a second bone.

Example 4 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-3, to optionally includethe first prosthetic component and the second prosthetic componentforming at least a portion of a prosthetic joint.

Example 5 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-4, to optionally includethe prosthetic joint includes at least one of a prosthetic ankle joint,a prosthetic wrist joint, a prosthetic elbow joint, a prosthetic kneejoint, a prosthetic hip joint, a prosthetic shoulder joint, a prostheticfinger joint, and a prosthetic toe joint.

Example 6 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-5, to optionally includethe cement applicator including a conduit sized and shaped to apply thebone cement into a void between the bone and the prosthetic component.

Example 7 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-6, to optionally includea frame configured to maintain a position or an alignment of theprosthetic component with respect to the bone or with respect to asecond prosthetic component.

Example 8 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-7, to optionally includeone or more components of the bone cement to be loaded into the cementapplicator.

Example 9 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-8, to optionally includea precursor of the bone cement including a liquid monomer and aparticulate copolymer.

Example 10 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-9, to optionally includeinstructions for using the prosthetic component and the cementapplicator.

Example 11 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-10, to optionally includethe instructions reciting the steps of positioning the prostheticcomponent adjacent to the bone, aligning the prosthetic component withrespect to the bone or with respect to another prosthetic component, andapplying the bone cement between the bone and the aligned prostheticcomponent.

Example 12 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-11, to optionally includethe instructions further reciting forming the mating profile in the boneby forming a male projecting feature or a female receiving feature.

Example 13 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-12, to optionally includethe instructions for applying the bone cement reciting applying the bonecement onto the male projecting feature or into the female receivingfeature after aligning the prosthetic component with respect to the boneor with respect to the other prosthetic component.

Example 14 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-13, to optionally includethe instructions further reciting a step of maintaining the alignment ofthe prosthetic component with respect to the bone or with respect to theother prosthetic component while applying the bone cement between theprosthetic component and the bone.

Example 15 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-14, to include subjectmatter (such as an apparatus, a device, a method, or one or more meansfor performing acts), such as can include a method of implant. Thesubject matter can include positioning a prosthetic component adjacentto a bone, aligning the prosthetic component with respect to the bone orwith respect to another prosthetic component, and applying a bone cementbetween the bone and the aligned prosthetic component.

Example 16 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-15, to optionally includeforming a bone feature on or in the bone, wherein the bone featurecorresponds to an attachment profile of the prosthetic component.

Example 17 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-16, to optionally includethe forming the bone feature including forming a male projecting featureor a female receiving feature.

Example 18 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-17, to optionally includethe applying the bone cement including applying the bone cement onto themale projecting feature or into the female receiving feature afteraligning the prosthetic component with respect to the bone or withrespect to the other prosthetic component.

Example 19 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-18, to optionally includethe applying the bone cement including injecting the bone cement througha conduit of a cement applicator and into or around a void between thebone and the aligned and attached prosthetic component.

Example 20 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-19, to optionally includethe applying the bone cement including applying the bone cement in aretrograde direction.

Example 21 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples to optionally include theattaching the prosthetic component to the bone including forming atleast a portion of a prosthetic joint selected from a prosthetic anklejoint, a prosthetic mist joint, a prosthetic elbow joint, a prostheticknee joint, a prosthetic hip joint, a prosthetic shoulder joint, aprosthetic finger joint, and a prosthetic toe joint.

Example 22 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-21, to optionally includeforming the bone cement, including mixing a monomer and a particulatecopolymer or a cement powder.

Example 23 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-22, to optionally includemaintaining the alignment of the prosthetic component with respect tothe bone or with respect to the other prosthetic component whileapplying the bone cement between the bone and the prosthetic component.

Example 24 can include, or can optionally be combined with the subjectmatter of one or any combination of Examples 1-23, to include subjectmatter (such as an apparatus, a device, a method, or one or more meansfor performing acts), such as can include a kit. The subject matter caninclude a prosthetic device for positioning adjacent to a bone andaligning with respect to the bone or with respect to another prostheticdevice, and cement for applying between the bone and the alignedprosthetic device.

The above detailed description includes references to the accompanyingdrawings, which form a part of the detailed description. The drawingsshow, by way of illustration, specific embodiments in which theinvention can be practiced. These embodiments are also referred toherein as “examples.” Such examples can include elements in addition tothose shown or described. However, the present inventors alsocontemplate examples in which only those elements shown or described areprovided. Moreover, the present inventors contemplate examples using anycombination or permutation of those elements shown or described (or oneor more aspects thereof), either with respect to a particular example(or one or more aspects thereof), or with respect to other examples (orone or more aspects thereof) shown or described herein.

In this document, the terms “a” or “an” are used, as is common in patentdocuments, to include one or more than one, independent of any otherinstances or usages of “at least one” or “one or more.” In thisdocument, the term “or” is used to refer to a nonexclusive or, such that“A or B” includes “A but not B,” “B but not A,” and “A and B,” unlessotherwise indicated. In this document, the terms “including” and “inwhich” are used as the plain-English equivalents of the respective terms“comprising” and “wherein.” Also, in the following claims, the terms“including” and “comprising” are open-ended, that is, a system, device,article, kit, composition, formulation, or process that includeselements in addition to those listed after such a term in a claim arestill deemed to fall within the scope of that claim. Moreover, in thefollowing claims, the terms “first,” “second,” and “third,” etc. areused merely as labels, and are not intended to impose numericalrequirements on their objects.

The above description is intended to be illustrative, and notrestrictive. For example, the above-described examples (or one or moreaspects thereof) may be used in combination with each other. Otherembodiments can be used, such as by one of ordinary skill in the artupon reviewing the above description. Also, various features or elementscan be grouped together to streamline the disclosure. This should not beinterpreted as intending that an unclaimed disclosed feature isessential to any claim. Rather, inventive subject matter can lie in lessthan all features of a particular disclosed embodiment. Thus, thefollowing claims are hereby incorporated into the detailed description,with each claim standing on its own as a separate embodiment. The scopeof the invention should be determined with reference to the appendedclaims, along with the full scope of equivalents to which such claimsare entitled.

The Abstract is provided to comply with 37 C.F.R. §1.72(b), to allow thereader to quickly ascertain the nature of the technical disclosure. Itis submitted with the understanding that it will not be used tointerpret or limit the scope or meaning of the claims.

1.-20. (canceled)
 21. A prosthesis positionable between a first bonesurface and a second bone surface in a patient, comprising: a prosthetictibial component comprising: a first attachment feature having a firstattachment profile that is associable with a mating profile of the firstbone surface in a male-female mating relationship; and a first articularsurface; a prosthetic talus component comprising: a second attachmentfeature having a second attachment profile that is associable with amating profile of the second bone surface in a male-female matingrelationship; and a second articular surface; and a bearing componentpositionable between the first articular surface of the prosthetictibial component and the second articular surface of the prosthetictalus component.
 22. The prosthesis of claim 21, wherein the firstattachment feature and the second attachment feature each extendsuninterruptedly from a first end to a second end.
 23. The prosthesis ofclaim 22, wherein the first attachment feature and the second attachmentfeature each comprises an elongated rail having a solid cross-sectionentirely formed of highly porous metal.
 24. The prosthesis of claim 22,wherein the first attachment feature and the second attachment featureextend across an entirety of the prosthetic tibial component and theprosthetic talus component, respectively.
 25. The prosthesis of claim21, wherein the attachment profile comprises a mushroom-shapedcross-sectional profile.
 26. The prosthesis of claim 21, wherein thefirst articular surface is concave and the second articular surface isconvex.
 27. The prosthesis of claim 26, wherein the second articularsurface subtends an arc segment greater than the first articularsurface.
 28. The prosthesis of claim 21, wherein: the prosthetic tibialcomponent and the prosthetic talus component each comprises: abearing-side substrate formed of a non-porous material; and abone-engaging structure attached to the bearing-side substrate andincluding the first or second attachment feature, the bone-engagingstructure comprising a porous material; and the bearing componentcomprises a polymeric material.
 29. The prosthesis of claim 21, whereinthe bearing component is couplable to either the prosthetic tibialcomponent or the prosthetic talus component.
 30. The prosthesis of claim29, wherein the bearing component is snap-fit to the prosthetic tibialcomponent.
 31. A prosthetic ankle implant comprising: a bone-engagingcomponent comprising: a bone-engaging structure; a first attachmentfeature projecting from the bone-engaging structure; and a bearing-sidesubstrate attached to the bone-engaging structure opposite the firstattachment feature; and a bearing component positionable against thebearing-side substrate.
 32. The prosthetic ankle implant of claim 31,wherein: the bone-engaging structure comprises a porous metallicmaterial; and the bearing component comprises a non-porous polymericmaterial.
 33. The prosthetic ankle implant of claim 31, wherein thebone-engaging component is arcuate such that the bearing-side substrateis concave.
 34. The prosthetic ankle implant of claim 33, wherein thebone-engaging component and the bearing component subtend arc segmentsof equal length.
 35. The prosthetic ankle implant of claim 34, whereinthe bone-engaging component is configured to join to a tibia.
 36. Theprosthetic ankle implant of claim 31, wherein the bone-engagingcomponent is arcuate such that the bearing-side substrate is convex. 37.The prosthetic ankle implant of claim 36, wherein the bone-engagingcomponent subtends an arc segment greater than an arc segment subtendedby the bearing component.
 38. The prosthetic ankle implant of claim 37,wherein the bone-engaging component is configured to join to a talus.39. The prosthetic ankle implant of claim 31, wherein the firstattachment feature comprises an elongated rail having a solidmushroom-like cross-sectional profile
 40. The prosthetic ankle implantof claim 39, wherein the first attachment feature extendsuninterruptedly from a first end to a second end across an entirety ofthe bone-engaging structure and is formed entirely of highly porousmaterial.